Organic light emitting display panel and manufacturing method thereof, display device

ABSTRACT

The present invention discloses an organic light emitting display panel and manufacturing method thereof and a display device, which can reduce the critical dimension bias of the pixel defining layer and improve the display uniformity. The organic light emitting display panel provide by the present invention comprises: a pixel defining layer, which is provided with a plurality of light emitting material filling areas, being characterized by further comprising: a metal layer provided on the pixel defining layer; the metal layer is provided with openings corresponding to the light emitting material filling areas respectively. The solutions provided by the present invention are used to improve the display effect of the organic light emitting display device.

RELATED APPLICATIONS

The present application is the U.S. national phase entry ofPCT/CN2015/091053, with an international filing date of Sep. 29, 2015,which claims the benefit of Chinese Patent Application No.201510227515.X, filed on May 6, 2015, the entire disclosures of whichare incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to the display field, and in particular toan organic light emitting display panel and manufacturing methodthereof, and a display device provided with the organic light emittingdisplay panel.

BACKGROUND

Organic light emitting display (OLED) has been deemed as a newlyemerging technology of the next generation of flat-panel displaysbecause of such excellent characteristics as self-emission, no need ofbacklight source, high contrast, small thickness, wide viewing angle,fast response time, possibility of using in a flexible substrate, wideoperating temperature range, simple structure and manufacturingprocesses etc.

An OLED display panel comprises a substrate, a (Indium Tin Oxide) (ITO)anode, a light emitting layer and a cathode etc., and its light emittingprinciple is that electrons and holes are recombined within the lightemitting layer to fall into a lower energy band under the effect of avoltage, and emit photons which have the same energy as the energy gap,and its wavelength (emission color) depends on the magnitude of theenergy gap of the light emitting layer. Therein, the light emittinglayer is generally manufactured by an inkjet printing technology inwhich a pixel defining layer (PDL) is required to be made on thesubstrate in advance to define the pixel areas into which ink dropletsare accurately sprayed. However, because the PDL is generally formedwith an organic material film by using a photolithography process, alarge exposure amount is required for the purpose of no photoresitresidues, thereby resulting in a large Critical Dimension bias (around2.0 μm). Moreover, it is further required that the organic material filmis cured after form formation and the curing process may cause theorganic material to contract such that the critical dimension biasfurther increases.

The above-mentioned Critical Dimension (referred to herein as “CD”) is aspecialized line pattern which is especially designed to indicate thewidth of feature lines of an integrated circuit for the purpose ofevaluating and controlling the pattern processing precision of theintegrated circuit photomask manufacturing and photolithography process.The critical dimension bias is the “After etch inspection CD” minus “theAfter develop inspection CD”, and is used for characterizing the etchingamount and the etching uniformity and therefore is a very important dataparameter during production which may be simply understood as thedifference between the etching design value and the etching actualvalue, i.e., the etching bias.

SUMMARY

An organic light emitting display panel and manufacturing method thereofand a display device seek to reduce the critical dimension bias of thepixel defining layer and improve the display uniformity of the displaypanel.

To this end, embodiments of the present invention utilize the followingtechnical solutions:

In certain exemplary embodiments, an organic light emitting displaypanel, comprises a pixel defining layer, which is provided with aplurality of light emitting material filling areas, and a metal layerprovided on the pixel defining layer; the metal layer is provided withopenings corresponding to the light emitting material filling areasrespectively.

In certain exemplary embodiments, the width of the opening is largerthan an opening width of the light emitting material filling area.

In certain exemplary embodiments, the distance from the edge of theopening to the edge of the light emitting material filling area on thesame side ranges from 1 to 3 μm.

The organic light emitting display panel further comprises lightemitting material filled in the light emitting material filling areas,and a second electrode and a first electrode provided above and belowthe light emitting material and electrically contacted with the lightemitting material respectively.

In certain exemplary embodiments, the second electrode is stacked on themetal layer and is arranged in parallel with the metal layer.

In certain exemplary embodiments, the second electrode is a cathode.

In certain exemplary embodiments, the metal layer is made of one or moreof the following materials: silver, aluminum, copper, nickel, chromiumand platinum.

In certain exemplary embodiments, the pixel defining layer is made ofone or more of the following material: polyimide, silicon oxide andsilicon nitride.

In certain exemplary embodiments, the surface of the metal layer ishydrophobic.

Embodiments of the present invention further provide a display device,comprising the organic light emitting display panel as described above.

In certain exemplary embodiments a manufacturing method of an organiclight emitting display panel, comprises forming a first electrode;forming a pixel defining material layer and curing the pixel definingmaterial layer; forming a patterned metal layer, the metal layer isformed with openings corresponding to preset light emitting materialfilling areas respectively; forming the light emitting material fillingareas in the pixel defining material layer below the openings by apatterning process; filling light emitting material and forming a secondelectrode.

In certain exemplary embodiments, the width of the opening is largerthan the opening width of the light emitting material filling area.

In certain exemplary embodiments, forming a patterned metal layercomprises directly forming the patterned metal layer by means of anevaporation way with the shielding of a mask; or forming a metalmaterial layer followed by forming the patterned metal layer by apatterning process.

In certain exemplary embodiments, the forming light emitting materialfilling areas in the pixel defining material layer below the openings bya patterning process comprises coating photoresist and performingexposure and development; performing dry etching to remove the pixeldefining material exposed to form the light emitting material fillingareas; peeling the remaining photoresist.

In certain exemplary embodiments, the pixel defining layer is made ofpolyimide; an etching gas used in the dry etching mainly comprisesoxygen, and further comprises CF4 or SF6, or a mixture of CF4 and SF6used for adjusting the etching slope angle.

In certain exemplary embodiments, when a photosensitive material is usedfor the pixel defining material layer, the forming light emittingmaterial filling areas in the pixel defining material layer below theopenings by a patterning process, comprises: coating photoresist andperforming exposure; peeling the photoresist and removing the exposedpixel defining material by an ashing process to form the light emittingmaterial filling areas.

In certain exemplary embodiments, before the process of forming a firstelectrode, the method further comprises: a process of forming an activelayer, a gate insulator layer, a gate metal layer and a source/drainmetal layer of a thin film transistor on a substrate; a process offorming an interlayer insulation layer and vias on the substrate onwhich the thin film transistor is formed.

The embodiments of present invention provides a display panel andmanufacturing method thereof, a display device, wherein a patternedmetal layer is provided on a pixel defining layer, the metal layer isprovided with openings corresponding to light emitting material fillingareas in the pixel defining layer respectively; while the pixel defininglayer is patterned, the above-mentioned metal layer and photoresist canbe used together as the mask for the pixel defining layer, therebyreducing the critical dimension bias of the pixel defining layer(referring to data from the comparison tests in the embodiments) andimproving display uniformity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a pixel defining layer and a metal layer on anorganic light emitting display panel according to an embodiment of thepresent invention;

FIG. 2 is a schematic cross-section view taken along the line A-A′ inFIG. 1;

FIG. 3 is a flow chart of a manufacturing method of an organic lightemitting display panel according to an embodiment of the presentinvention;

FIG. 4 is a schematic cross-section view of an organic light emittingdisplay panel according to an embodiment of the present invention;

FIGS. 5(a) to 5(j) are schematic views of manufacturing processes of anorganic light emitting display panel according to an embodiment of thepresent invention.

DESCRIPTION OF REFERENCE SIGNS

10—substrate, 101—transition layer, 102—active layer, 103—gate insulatorlayer, 104—gate metal layer, 105—insulation layer, 106—source/drainelectrode layer, 107—planarization layer, 108—interlayer insulationlayer, 11—anode, 12—pixel defining layer, 121—light emitting materialfilling areas, 13—metal layer, 14—light emitting material, 15—cathode,120—pixel defining material layer, 130—metal film, 200—photoresist,300—photoresist.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention provide an organic light emittingdisplay panel and a manufacturing method thereof and a display devicewhich can reduce the critical dimension bias of the pixel defining layerand improve the display uniformity.

The following detailed description for the embodiments of the presentinvention will be provided in combination with the drawings.

Embodiments described herein are merely for explaining the presentinvention and are not intended to limit the present invention.

Embodiments of the present invention provide an organic light emittingdisplay panel. As shown in FIG. 1 and FIG. 2, the panel comprises: apixel defining layer 12 which is provided with a plurality of lightemitting material filling areas 121. The panel further comprises: ametal layer 13 provided on the pixel defining layer 12; and the metallayer 13 is provided with openings 131 corresponding to the lightemitting material filling areas 121 respectively.

An organic light emitting display panel generally comprises a substrate,an anode 11 of ITO (Indium Tin Oxide), light emitting material and ancathode etc. (FIGS. 1 and 2 merely show the layers related to thepresent invention, such as the pixel defining layer 12 and the metallayer 13), wherein the light emitting material is formed in the lightemitting material filling areas 121 within the pixel defining layer 12.In this embodiment, the pixel defining layer 12 is overlaid with themetal layer 13 on which openings 131 (i.e., the patterned metal layer13) are provided to correspond to the light emitting material fillingareas 121 respectively, and herein the centers of openings 131 of theupper metal layer 13 are preferably aligned with those of openings ofthe lower light emitting material filling areas 121. The purpose of theopenings 131 provided on above-mentioned metal layer 13 is: when thepixel defining layer 12 is etched to form the light emitting materialfilling areas 121, the metal layer 13 can be used as the mask for thepixel defining layer 12 to reduce the critical dimension bias of thepixel defining layer 12. In this design, the space reserved for thecritical dimension bias may be designed as smaller so that the lightemitting material filling areas 121 may occupy relatively larger spaceon the panel thereby improving the display uniformity.

In this embodiment, the metal layer 13 has openings 131, that is, themetal layer 13 has hollow structures at the locations corresponding tothe light emitting material filling areas 121.

It should be noted that, the more conformal the patterns of the metallayer 13 and the pixel defining layer 12 are, the smaller the criticaldimension bias of the pixel defining layer 12 will be reduced; however,the bottom of the light emitting material filling areas 12 are providedwith an electrode (for example, the anode 11 in the figure), it isrequired that the openings 131 of the metal layer 13 are preferablydesigned to be relatively large, that is, the distribution range towhich the openings 131 correspond should be larger than the distributionrange to which the light emitting material filling areas 121 correspond,in order to prevent the metal layer 13 from extending into the lightemitting material filling areas 121 to be in contact with the electrodeat the bottom to cause a short circuit. In practice, if the lightemitting material filling areas 121 have a structure being narrow in theopening and wide at the bottom, the distribution range to which thelight emitting material filling areas 121 correspond is subject to thesize of their openings, i.e., it should be generally guaranteed that thedistribution range to which the openings 131 correspond is larger thanthe opening range of the light emitting material filling areas 121.Those skilled in the field could adjust the size of the openings 131 ofthe metal layer 13 according to a practical situation, as long as itmakes sure that the metal layer 13 is not short to the electrode at thebottom of the light emitting material filling areas 121.

In practice, the distribution range to which the openings 131 correspondmay be measured with a opening width in a certain direction, that is,the opening width of the openings 131 is larger than the opening widthof the light emitting material filling areas 121. As shown in FIG. 2, inthe direction of A-A′ in FIG. 1, the opening width of the metal layer 13is M, and the opening width of the light emitting material filling areas121 is T. With the current process level, the distance L (L=T−M) fromthe edge of openings of the metal layer 13 to the edge of the lightemitting material filling areas 121 on the same side may be generallyset to 1-3 μm, wherein L is optimally set to 2 μm which not only makessure of no short circuit occurring but also minimizes the criticaldimension bias of the pixel defining layer 12.

Moreover, the above-mentioned organic light emitting display panelfurther comprises: light emitting material filled in the light emittingmaterial filling areas 121, a second electrode and a first electroderespectively provided above and below the light emitting material andelectrically contact with the light emitting material respectively; andthe to metal layer 13 may be connected in parallel to the firstelectrode or the second electrode.

In this embodiment, the metal layer 13 may be connected in parallel tothe first electrode or the second electrode so as to reduce theresistance of the electrode. Because of the complexity of LTPS (LowTemperature Poly-silicon) process, the way of adding assistant wires inother layers to be connected in parallel with the electrodes would causeincreased risk of short circuit. By contrast, in this embodiment, themetal layer 13 on the pixel defining layer 12 is used as the parallelresistor and the pixel defining layer 12 can function as an insulator sothat the risk of short circuit can be reduced.

In the embodiment, the metal layer 13 may be directly stacked above orbelow the first electrode (or the second electrode). Alternatively,other intermediate films may be provided between the metal layer 13 andthe first electrode so that the metal layer 13 realizes the parallelconnection by vias running throughout these intermediate films. In thisembodiment, one of the first and second electrodes is an anode and theother is a cathode, and the metal layer 13 may be connected in parallelwith the cathode or the anode and act as a parallel resistor to reducethe resistance of the electrode. However, preferably, the metal layer 13is selectively connected in parallel with the second electrode above thelight emitting material for the reason that the second electrode islocated above the light emitting material and generally provided in theform of a whole covering layer so that the parallel connection isachieved by directly stacking the metal layer 13 on the metal layer 13without additional processes to achieve the parallel connection.

The above-mentioned metal layer 13 may be made from one or more of thefollowing materials: silver, aluminum, copper, nickel, chromium andplatinum. The specific implementation is not limited to the above metalsas long as the resistivity is small enough to meet the designrequirements, and there is no limit on how the above mentioned metalmaterials are used to form the metal layer 13 in this embodiment; one ofthe above-mentioned metal materials may be independently used to formthe metal layer 13; two or more materials of the above mentioned metalmaterials may be also used in an alloy form to form the metal layer 13;the metal layer 13 may be also formed by stacking a plurality of filmswith each other, wherein each film is formed of one or more materials ofthe above-mentioned metals. The above-mentioned pixel defining layer 12may be formed by one or more of the following materials: polyimide,silicon oxide and silicon nitride. Also, there is no limit on how theabove-mentioned materials are used to form the pixel defining layer 12in this embodiment, that is, one of the above materials may beindependently used to form the pixel defining layer 12; the pixeldefining layer 12 may be also formed by stacking a plurality of filmswith each other, wherein each film may be formed by one or more of theabove materials.

In addition, in the embodiment, the metal layer 13 is provided on thetop of the pixel defining layer 12. Preferably, the surface of the metallayer 13 is hydrophobic, or is formed by a hydrophobic material, or isobtained with a hydrophobic process on the surface. By contrast, theexisting light emitting material is generally hydrophilic such that whenthe pixel defining layer 12 is formed with the printing method, thelight emitting material may form droplets which eventually flow into thelight emitting material filling areas 121, even if the printing deviatesfrom the pixel regions, thereby reducing the cost and facilitating massproductions.

Embodiments of the present invention also provide a manufacturing methodof an organic light emitting display panel, as shown in FIG. 3, themethod comprises:

101. forming a first electrode;

Generally, the main component of an organic light emitting display panelis the light emitting device, the main structure of which is formed fromtwo electrodes with electroluminescent material (which is referred asthe light emitting material in the embodiment) disposed therebetween, inparticular, is formed as a sandwich structure from a thin andtransparent tin indium oxide (ITO) having semiconductor properties,another metal anode and electroluminescent material deposed between theboth (i.e., tin indium oxide and metal anode). In this step of formingthe first electrode of the light emitting device, the approach offirstly forming a film and then patterning the film by thephotolithography technology is generally used; however, there is nolimit on the specific implementation of this step which may be any wayswell known by those skilled in the art.

102. forming a pixel defining material layer and curing the pixeldefining material layer;

This step is a filming process of the pixel defining layer 12 which mayutilize any filming ways such as coating, evaporating, sputtering,chemical vapor deposition and so on.

103. form a patterned metal layer 13, wherein the metal layer 13 isformed with openings 131 corresponding to the preset light emittingmaterial filling areas respectively.

This step is to pattern the metal layer 13 such that the metal layer 13is formed with openings 131 corresponding to the preset light emittingmaterial filling areas respectively. In practice, the step may comprisesthe evaporating method with the shielding of a mask to directly form apatterned metal layer; alternatively, comprises firstly forming a metalmaterial layer and then forming a patterned metal layer by a patterningprocess. The latter generally uses the photolithography process in whicha photoresist is firstly coated, exposed and developed in preset openingareas to form windows with photoresist fully peeled, and the metal layer13 exposed at the windows is etched with an appropriate etchant to formopenings 131.

104. forming light emitting material filling areas 121 in the pixeldefining material layer below the openings 131 by a patterning process;

The step is to pattern the pixel defining material layer to form thelight emitting material filling areas 121, which may be alsoaccomplished by using the photolithography process, but differ in thatthe step is generally to use the dry etching which includes but notlimited to sputtering and ion beam milling, reactive ion etching (RIE),high density plasma etching (HDP), plasma etching and high pressureplasma etching.

This step generally comprises: a photoresist is coated, exposed anddeveloped, wherein the exposed areas correspond to openings 131 on themetal layer 13 respectively; the pixel defining material exposed isremoved by using the dry etching to form the light emitting materialfilling areas 121, wherein the etching gas used in the dry etchingfurther comprises components used for adjusting the etching slope angleto reduce segment difference and thus prevent the upper layer (forexample at which the second electrode is located) from cracking due toexcessive segment difference; the remaining photoresist is peeled.

If a photosensitive material is used for the pixel defining materiallayer, this step may also use the following processes instead of the dryetching, comprising: coating a photoresist and performing the exposure;peeling the photoresist and removing the exposed pixel defining materialby an ashing process to form the light emitting material filling areas121. In addition, it should be noted that, preferably, the opening widthof the light emitting material filling areas 121 formed in this step issmaller than the opening width of the openings 131 of the metal layer inorder to prevent the metal layer 13 from being short to the firstelectrode, as shown in FIG. 2, that is, the exposed areas should notexceed the predetermined range of the light emitting material fillingareas 121. Moreover, in the exposure process of the patterning processin this step, the patterned metal layer formed in step 103 can functionas the mask which is helpful to eventually reduce the critical dimensionbias of the pixel defining layer 12.

105. filling the light emitting material and forming a second electrode.

In this step, filling the light emitting material into the lightemitting material filling areas 121 may include but not limited to theevaporating or printing process. This step further comprises forming thesecond electrode which is similar to the step in prior art and notrepeated herein.

In addition, the manufacturing method of the organic light emittingdisplay panel described in this embodiment, before the process offorming a first electrode, further comprises: a process of forming anactive layer, a gate insulator layer, a gate metal layer and asource/drain metal layer of a thin film transistor on a substrate; aprocess of forming an interlayer insulation layer and vias on thesubstrate on which the thin film transistor is formed. The methodfurther comprises a packaging process etc. following the step 105.

In this embodiment of the metal layer 13 provided on the pixel defininglayer 12, a pixel defining material is firstly deposited and thenpatterned to form the metal layer 13 (i.e., the metal layer havingopenings 131) and light emitting material filling areas 121 are formedby dry etching at the openings 131 in the metal layer such that thecritical dimension bias can be reduced; in addition, the secondelectrode is stacked with the metal layer 13 which may also act as theresistor connected in parallel with the electrode to reduce theresistance of the electrode.

In order to make sure that those skilled in the field better understandthe structure of the organic light emitting display panel and themanufacturing method thereof, the following specific embodiments will bedescribed in detail.

As shown in FIG. 4, an organic light emitting display panel provided byone embodiment of the present invention comprises: a substrate 10, atransition layer 101 and a patterned active layer 102 (used to formchannels of TFT) provided in sequence on the substrate 10, a gateinsulator layer 103 and a patterned gate metal layer 104 provided on theactive layer 102 (including the gate of TFT, gate lines and otherconnecting wires required to be formed in this layer in the drivingcircuit); an insulation layer 105 deposited on the gate metal layer 104,a patterned source/drain electrode layer 106 formed on the insulationlayer 105, wherein the source/drain electrode layer 106 includes asource, a drain of TFT, data signal lines and other connecting wiresrequired to be formed in this layer in the driving circuit, and thesource and drain of TFT are respectively connected to the active layer102 by vias in the insulation layer 15; a planarization layer 108 and aninterlayer insulation layer 107 provided on the source/drain electrodelayer 106 to reduce segment difference and achieve interlayerinsulation; an anode 11 provided on the interlayer insulation layer 107,wherein the anode 11 is connected with the drain of the driving TFTthrough vias; a pixel defining layer 12 provided on the anode 11,wherein the pixel defining layer 12 is provided with light emittingmaterial filling areas 121 at the locations corresponding to the anode11 and the light emitting material filling areas 121 are filled withlight emitting material 14; a metal layer 13, a cathode 15 and otherpackage film layers (which are not shown in figures) provided insequence on the pixel defining layer 12.

In this embodiment, the metal layer 13 is of silver or aluminum; thepixel defining layer 12 is formed by Polyimide (PI); the active layer102 is of amorphous silicon material; a cathode material layer (i.e.,the cathode 15 of the light emitting device) is stacked on the metallayer 13 and connected in parallel to the metal layer 13.

Hereafter, the general processes of manufacturing the above-mentionedorganic light emitting display panel will be briefly described incombination with this specific embodiment:

In Step 1, forming a transition layer 101, an amorphous silicon layerP—Si (corresponding to the active layer 102 in the drawings), a gateinsulator (GI) layer 103, a gate metal layer 104, an insulation layer105, a source/drain electrode layer 106, a planarization layer 108, aninterlayer insulation layer 107, an anode electrode layer (correspondingto the anode 11 in the drawings) in sequence on a glass substrate, andcoating and curing a layer of pixel defining material (corresponding tothe pixel defining material layer 120 in the drawings), as shown in FIG.5(a); a layer of Ag or Al metal is then formed by the sputtering process(corresponding to the metal film 130 in the drawings), as shown in FIG.5(b). The organic light emitting display panel is manufactured along thedirection indicated by the arrow in the drawing, and the arrangementsequence in FIGS. 5(a) to 5(j) is determined accordingly.

In Step 2, forming the patterns of openings 131 corresponding to the tolight emitting material filling areas 121 on the metal film 130 (i.e.,Ag or Al metal) by the patterning process. In this step, a metal isfirstly deposited and then a photoresist 200 is coated on the metallayer, and exposure, development and etching etc. are performed, asshown in FIG. 5(c). In the etching step, Ag or Al metal is etched withthe wet etching process. The optional etchants may include componentssuch as phosphoric acid, acetic acid, nitric acid, other additives andwater etc., and there is no limit on the etching time which may be setaccording to requirements from different equipments.

In Step 3, a photoresist coating process is performed again on thephotoresist 200 to form a photoresist 300, as shown in FIG. 5(d);performing the exposure and development steps to form windows with thephotoresist fully removed, as shown in FIG. 5 (e); then performing thedry etching to the pixel defining material layer 120 at the windows, andFIG. 5(f) shows the result after the dry etching. The etching gas mainlyincludes oxygen which may be added with an appropriate amount of CF₄ orSF₆ for adjusting the slope angle, and there is no limit on thepressure, power and time of etching which may be adjusted according torequirements from various equipments. The slope angle of the pixeldefining layer 12 is adjusted by adding CF₄ or SF₆ gas to increase theimpact such that the slope angle can be changed and the segmentdifference is adjusted.

In Step 4, then, as shown in FIG. 5(j), peeling the photoresist 200, 300and proceeding to the subsequent processes to finish the panel.

In order to further demonstrate that the metal layer 13 functions toreduce the critical dimension bias of the pixel defining layer 12,results from comparison tests are listed as follows:

The test 1 uses PI to form the critical dimension pattern (the priorart) and Table 1 shows that the pattern formed in the test 1 is measuredat 7 different locations and compared to the design values to obtain theBias data wherein the minimum value is 1.51 μm, the maximum value is2.73 μm and the average value is 2.00 μm.

The test 2 is to make the critical dimension pattern by the method offorming the pixel defining layer and metal layer mentioned in theembodiment of the present invention (see related parts of Step 1 to 3),wherein PI film forming and various process parameters inphotolithography are exactly identical to those in test 1 and PI patternis also the same. Table 2 shows that the pattern formed in test 2 ismeasured at 7 different locations to calculate Bias data wherein theminimum value is 1.35 μm, the maximum value is 2.63 μm and the averagevalue is 1.94 μm.

It can be seen from the comparison that, the critical dimension bias ofthe pixel defining layer can be reduced from 2.0 μm to around 1.94 μm bymeans of the structure of the organic light emitting display panel andmanufacturing method thereof provided by this embodiment, and thereforethe aperture ratio and display uniformity can be improved accordingly.

TABLE 1 Test 1 Material Thickness Critical dimension bias (μm) 1st unittest PI 1.5 μm 2.73 2nd unit test PI 1.5 μm 1.86 3rd unit test PI 1.5 μm2.31 4th unit test PI 1.5 μm 1.70 5th unit test PI 1.5 μm 2.18 6th unittest PI 1.5 μm 1.72 7th unit test PI 1.5 μm 1.51 Average 2.00

TABLE 2 Test 2 Material Thickness Critical dimension bias (μm) 1st unittest Ag 1000 Å 2.50 2nd unit test Ag 1000 Å 2.63 3rd unit test Ag 1000 Å1.35 4th unit test Ag 1000 Å 1.77 5th unit test Ag 1000 Å 2.18 6th unittest Ag 1000 Å 1.35 7th unit test Ag 1000 Å 1.82 Average 1.94

Embodiments of the present invention also provide a display device thatcomprises any one of the above-mentioned organic light emitting displaypanels, which is capable of reducing the critical dimension bias of thepixel defining layer and thereby improving the aperture ratio anddisplay uniformity; meanwhile the parallel connection of the metal layerwith the electrode further decreases the resistance of the electrode andreduces the power consumption of the display device. Moreover, themanufacturing processes are simple without need of additional processesused to form wires connected in parallel with the electrode fordecreasing the resistance of the electrode such that the cost can bereduced which is in favor of mass production. Said display device maybe: any product or part having the displaying function, such as OLEDpanel, electronic paper, mobile phone, tablet computer, television,display, notebook computer, digital photo frame, and navigator and soon.

Technical features described in embodiments of the present invention maybe arbitrarily combined with each other in no conflict scenario.

It should be noted that, while embodiments of the present invention havebeen illustrated with the manufacturing processes of the light emittinglayer of the organic light emitting display panel as an example, thepresent invention is not limited to this embodiment; rather, the presentinvention can be widely applied to the application in which the criticaldimension bias of one layer is required to be decreased and a metallayer can be designed on the layer.

The above description is only the specific embodiments of the presentinvention, but the scope of the present invention is not limited tothis. In the technical scope disclosed by the invention, any skilled inthe art can easily appreciate modifications or replacements which shouldfall within the scope of the invention. Accordingly, the scope of thepresent invention should be defined by the scope of the claims.

1-17. (canceled)
 18. An organic light emitting display panel,comprising: a pixel defining layer having a plurality of light emittingmaterial filling areas, and a metal layer provided on the pixel defininglayer; wherein the metal layer is provided with openings correspondingto the light emitting material filling areas.
 19. The organic lightemitting display panel of claim 18, wherein the width of the opening islarger than an opening width of the light emitting material area. 20.The organic light emitting display panel of claim 19, wherein thedistance from the edge of the openings to the edge of the light emittingmaterial filling areas on the same side is in the range from 1 to 3 μm.21. The organic light emitting display panel of claim 18, furthercomprising: light emitting material filled in the light emittingmaterial filling areas, a second electrode above the light emittingmaterial, and a first electrode below the light emitting material,wherein both the first and second electrode are electrically contactedwith the light emitting material.
 22. The organic light emitting displaypanel of claim 21, wherein the second electrode is stacked on the metallayer and is connected in parallel with the metal layer.
 23. The organiclight emitting display panel of claim 22, wherein the second electrodeis a cathode.
 24. The organic light emitting display panel of claim 18,wherein the metal layer comprises at least one of silver, aluminum,copper, nickel, chromium and platinum.
 25. The organic light emittingdisplay panel of claim 18, wherein the pixel defining layer comprises atleast one of polyimide, silicon oxide and silicon nitride.
 26. Theorganic light emitting display panel of claim 18, wherein the surface ofthe metal layer is hydrophobic.
 27. A display device comprising: theorganic light emitting display panel of claim
 18. 28. A method ofmanufacturing an organic light emitting display panel comprising:forming a first electrode; forming a pixel defining material layer andcuring the pixel defining material layer; forming a patterned metallayer with openings corresponding to preset light emitting materialfilling areas respectively; forming light emitting material fillingareas in the pixel defining material layer below the openings by apatterning process; filling light emitting material; and forming asecond electrode.
 29. The method of claim 28, wherein the width of theopening is larger than an opening width of the light emitting materialfilling area.
 30. The method of claim 28, wherein the step of forming apatterned metal layer comprises: directly forming the patterned metallayer using an evaporation method with the shielding of a mask; orforming a metal material layer followed by forming the patterned metallayer by a patterning process.
 31. The method of claim 29, wherein thestep of forming a patterned metal layer comprises: directly forming thepatterned metal layer by means of an evaporation method with theshielding of a mask; or forming a metal material layer followed byforming the patterned metal layer by a patterning process.
 32. Themethod of claim 28, wherein the forming light emitting material fillingareas in the pixel defining material layer below the openings by apatterning process comprises: coating a photoresist and performingexposure and development; performing dry etching to remove the pixeldefining material exposed and form the light emitting material fillingareas; peeling the remaining photoresist.
 33. The method of claim 29,wherein the step of forming light emitting material filling areas in thepixel defining material layer below the openings by a patterning processcomprises: coating a photoresist and performing exposure anddevelopment; performing dry etching to remove the pixel definingmaterial exposed and form the light emitting material filling areas;peeling the remaining photoresist.
 34. The method of claim 32, whereinthe pixel defining layer comprises polyimide; the etching gas used inthe dry etching comprises oxygen, and further comprises CF4 or SF6, or amixture of CF4 and SF6 used for adjusting an etching slope angle. 35.The method of claim 28, wherein when a photosensitive material is usedfor the pixel defining material layer, the step of forming lightemitting material filling areas in the pixel defining material layerbelow the openings by a patterning process comprises: coating aphotoresist and performing exposure; peeling the remaining photoresistand removing the exposed pixel defining material by an ashing process toform the light emitting material filling areas.
 36. The method of claim29, wherein when a photosensitive material is used for the pixeldefining material layer, the step of forming light emitting materialfilling areas in the pixel defining material layer below the openings bya patterning process comprises: coating a photoresist and performingexposure; peeling the remaining photoresist and removing the exposedpixel defining material by an ashing process to form the light emittingmaterial filling areas.
 37. The method of claim 28, wherein before theprocess of forming a first electrode, the method further comprises: aprocess of forming an active layer, a gate insulator layer, a gate metallayer and a source/drain metal layer of a thin film transistor on asubstrate; a process of forming an interlayer insulation layer and viason the substrate on which the thin film transistor is formed.